2017 YAMAHA YS125 diagnostic

Table of contents
Replacing the fuse.........................6-31
Replacing the headlight bulb.........6-33
Replacing the auxiliary light
bulb ...........................................6-34
Replacing the brake/tail light
bulb ............................................6-35
Replacing a turn signal light bulb ............................................6-35
Replacing the license plate light bulb ............................................6-36
Front wheel....................................6-36
Rear wheel.....................................6-37
Troubleshooting ............................6-39
Troubleshooting chart ...................6-41
Motorcycle care an d stora ge ..........7-1
Matte color caution .........................7-1
Care .................................................7-1
Storage ............................................7-3
Specifications ....................................8-1
Consumer information .....................9-1
Identification numbers .....................9-1
Diagnostic connector ......................9-2
Vehicle data recording ....................9-2
In dex ................................................10-1
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Instrument and control functions
3-2
3
To unlock the steering
Insert the key and turn it to “ ”.
EAU1100D
In
dicator li ghts an d warnin g
lig ht
EAU11022
Turn si gnal in dicator li ght “ ”
This indicator light flashes when a turn
signal light is flashing.
EAU11061
Neutral in dicator li ght “ ”
This indicator light comes on when the
transmission is in the neutral position.
EAU11081
Hi gh beam in dicator li ght “ ”
This indicator light comes on when the
high beam of the headlight is switched
on.
EAU78310
En gine trou ble warnin g li ght “ ”
This warning light comes on if a prob-
lem is detected in the engine or other
vehicle control system. If this occurs,
have a Yamaha dealer check the on-
board diagnostic system.
The electrical circuit of the warning
light can be checked by turning the key
to “ ”. The warning light should come
on for a few seconds, and then go off.
If the warning light does not come on
initially when the key is turned to “ ”,
or if the warning light remains on, have
a Yamaha dealer check the vehicle.
EAUE2572
Eco in dicator li ght “ECO”
This indicator light comes on when the
vehicle is being operated in an environ-
mentally friendly, fuel-efficient manner.
The indicator light goes off when the
vehicle is stopped.
1. Turn.
1
1. Turn signal indicator light “ ”
2. Neutral indicator light “ ”
3. High beam indicator light “ ”
4. Eco indicator light “ECO”
5. Engine trouble warning light “ ”
1
2
3
4
5
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Periodic maintenance an d a djustment
6-4
6
EAU71342
General maintenance an d lu brication chartNO. ITEM CHECK OR MAINTENANCE JOB ODOMETER READING
ANNUAL
CHECK
1000 km
(600 mi) 6000 km
(3500 mi) 12000 km
(7000 mi) 18000 km
(10500 mi) 24000 km
(14000 mi)
1 *Dia
gnostic system
check • Perform dynamic inspection us-
ing Yamaha diagnostic tool.
• Check the error codes. √√√√√√
2 *Air filter element • Clean.
√√
•Replace. √√
3 Air filter case check
hose
• Clean.
√√√√√
4Clutch • Check operation.
•Adjust.
√√√√√
5 *Front brake • Check operation, fluid level, and
for fluid leakage.
• Replace brake pads if necessary. √√√√√√
6 *Rear brake • Check operation.
• Adjust brake pedal free play.
• Replace brake shoes if neces-
sary. √√√√√√
7 *Brake hose • Check for cracks or damage.
√√√√√
• Replace. Every 4 years
8 *Brake flui d • Change. Every 2 years
9 *Wheels • Check runout and for damage.
• Replace if necessary.
√√√√
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Consumer information
9-2
9
The model label is affixed to the frame
behind panel A. (See page 6-8.) Re-
cord the information on this label in the
space provided. This information will
be needed when ordering spare parts
from a Yamaha dealer.
EAU69910
Dia
gnostic connectorThe diagnostic connector is located as
shown.
EAU74701
Vehicle data recor din gThis model’s ECU stores certain vehi-
cle data to assist in the diagnosis of
malfunctions and for research and de-
velopment purposes. This data will be
uploaded only when a special Yamaha
diagnostic tool is attached to the vehi-
cle, such as when maintenance checks
or service procedures are performed.
Although the sensors and recorded
data will vary by model, the main data
points are:
 Vehicle status and engine perfor-
mance data
 Fuel-injection and emission-relat-
ed data
Yamaha will not disclose this data to a
third party except:  With the consent of the vehicle
owner
 Where obligated by law
 For use by Yamaha in litigation
 For general Yamaha-conducted
research purposes when the data
is not related to an individual vehi-
cle nor owner
1. Diagnostic connector
1
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10-1
10
IndexAAir filter element and check hose,
cleaning .............................................. 6-14
Auxiliary light bulb, replacing ................ 6-34BBattery .................................................. 6-30
Brake and clutch levers, checking and lubricating ........................................... 6-27
Brake and shift pedals, checking and
lubricating ........................................... 6-26
Brake fluid, changing ............................ 6-23
Brake fluid level, checking .................... 6-22
Brake lever .............................................. 3-7
Brake lever free play, checking............. 6-20
Brake light switches.............................. 6-21
Brake pads and shoes, checking ......... 6-22
Brake pedal............................................. 3-7
Brake pedal free play, adjusting ........... 6-21
Brake/tail light bulb, replacing .............. 6-35CCables, checking and lubricating ......... 6-26
Care ........................................................ 7-1
Catalytic converters .............................. 3-10
Centerstand and sidestand, checking and lubricating .................................... 6-28
Clutch lever ............................................. 3-6
Clutch lever free play, adjusting ........... 6-19
Cowling and panels, removing and installing................................................ 6-8DData recording, vehicle ........................... 9-2
Diagnostic connector.............................. 9-2
Dimmer switch ........................................ 3-5
Drive chain, cleaning and lubricating .... 6-25 Drive chain slack .................................. 6-24
EEco indicator light................................... 3-2
Engine break-in ...................................... 5-3
Engine idling speed .............................. 6-16
Engine oil and oil filter element ............ 6-11
Engine serial number .............................. 9-1
Engine trouble warning light ................... 3-2FFront fork, checking ............................. 6-29
Fuel ......................................................... 3-8
Fuel consumption, tips for reducing ...... 5-3
Fuel tank cap .......................................... 3-8
Fuse, replacing ..................................... 6-31HHandlebar switches ................................ 3-5
Headlight bulb, replacing ..................... 6-33
High beam indicator light ....................... 3-2
Horn switch ............................................ 3-5IIdentification numbers ............................ 9-1
Ignition circuit cut-off system ............... 3-13
Indicator lights and warning light ........... 3-2LLicense plate light bulb, replacing........ 6-36MMain switch/steering lock....................... 3-1
Maintenance and lubrication, periodic ... 6-4
Maintenance, emission control
system.................................................. 6-3
Matte color, caution ............................... 7-1
Model label ............................................. 9-1
Multi-function meter unit ........................ 3-3
NNeutral indicator light ..............................3-2PParking ....................................................5-4
Part locations ..........................................2-1
Pass switch .............................................3-5SSafety information ...................................1-1
Seat .......................................................3-11
Shifting ....................................................5-2
Shift pedal ...............................................3-6
Shock absorber assemblies, adjusting .............................................3-11
Sidestand ..............................................3-12
Spark plug, checking ............................6-10
Specifications .........................................8-1
Starting the engine ..................................5-1
Start switch .............................................3-6
Steering, checking ................................6-29
Storage ...................................................7-3
Swingarm pivots, lubricating ................6-28TThrottle grip and cable, checking and lubricating ...........................................6-26
Throttle grip free play, checking ...........6-16
Tires ......................................................6-17
Tool kit ....................................................6-2
Troubleshooting ....................................6-39
Troubleshooting chart ...........................6-41
Turn signal indicator light........................3-2
Turn signal light bulb, replacing ............6-35
Turn signal switch ...................................3-5VValve clearance .....................................6-17
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